Method of manufacturing a head gimbal assembly with substantially orthogonal tab, side beam and base

ABSTRACT

Methods of manufacturing a load beam including a flexure/slider assembly are provided. A pre-form of a load beam has a base, a side beam extending from the base and a tab extending from the side beam, all substantially in a common plane. The flexure/slider assembly is attached to the base, then the load beam is bent in two locations, between the tab and the side beam, and between the side beam and the base. After bending, the tab and the side beam are substantially orthogonal to one another and both the tab and the side beam are substantially orthogonal to the base so that the base, side beam, and tab form a partial enclosure around the slider.

This application is a divisional of U.S. application Ser. No. 09/413,614filed on Oct. 6, 1999, now U.S. Pat. No. 6,538,850, and claims prioritytherefrom pursuant to 35 U.S.C. §120.

BACKGROUND OF THE INVENTION

As computers have improved over recent years the need for increased datastorage has risen dramatically. To meet this need several approacheshave been taken to make disk drives capable of storing more data withoutincreasing, and in some cases actually decreasing, their overall size.One approach has been to raise the recording density of the disks bystoring more data on the same size disk. Another approach has been toincrease the number of disks in the drive's disk stack by spacing thedisks closer together.

Increasing the recording density primarily depends on reducing theamount of disk space needed to store each bit of data. A disk drivestores and retrieves data by using a magnetic head which writes dataonto the disk by aligning magnetic poles in the magnetic material andreads data by sensing the alignment of previously written poles. Thesmaller the poles can be made, the more data that can be stored on thedisk. However, as the poles are made smaller, the magnetic fieldsproduced by the poles become weaker. Thus, to align and sense the poles,the magnetic head has to be kept very near the surface of the disk.

In order to position magnetic heads sufficiently close to the surface ofdisks, the heads are typically mounted to air bearing sliders. An airbearing slider is a device which is specifically shaped so that whenplaced into the airstream existing near the surface of a rotating disk,the slider will provide a lifting force, to cause it to fly just abovethe disk surface. As magnetic heads are normally much smaller thansliders, they can be mounted to and flown along with the slider. Thisallows the distance between the magnetic head and the disk surface to bekept relatively small and constant.

Usually, the slider is part of a head gimbal assembly which is attachedto an actuator or support arm. As the support arm reciprocates, theslider is moved across the disk surface to precise positions overindividual data tracks on the disk. The head gimbal assembly includes apivot point and a flexure. As the name implies, the flexure isordinarily a flexible piece of metal, which is stiff enough to urge theslider to maintain a desired position relative to the disk surface, butflexible enough to allow the slider to pitch and roll about the pivotpoint. It is important that the slider can move about the pivot point sothat the slider can freely fly above the disk.

Unfortunately, flying a slider close to the disk surface increases thepotential for damage caused by the slider contacting the disk surface.Contact between the slider and disk can result from a shock, jolt orbump to the disk drive, or from the process of loading and unloading theslider between uses. Depending on the flying height of the slider, evena relatively minor shock can displace the slider enough to cause it tocollide with the disk surface. Also, an external shock or jolt to thedisk drive can cause structural damage to the flexure if the slider isdisplaced too far about, or from, the pivot point or if the flexure isloaded excessively. Such shocks or jolts can also occur during themanufacturing process when the disk drive is assembled. Damage to theflexure can include dimple separation and bending of the flexure. Dimpleseparation can occur if the flexure/slider assembly separates too farfrom the pivot point and deforms the flexure into its plastic range.With dimple separation the flexure no longer can maintain the slider incontact with the pivot point or even if contact can be maintained itcannot be done with the same resiliency.

Thus, to allow for the low flying heights required to achieve higherrecording density, an apparatus is needed which will limit or preventdamage caused by shocks, jolts or bumps. However, such an apparatusshould also allow for load/unload operations.

To increase recording density and to improve the head-disk interface (toreduce wear to the slider and surface of the disk and to reduce stictionbetween the slider and disk), load/unload operations have been employed.As the name implies, a load/unload operation involves unloading andloading steps. The “unload” portion of a load/unload operation involvesphysically lifting and retaining the head gimbal assembly (with theslider) up and away from the surface of the disk. Unloading is done tokeep the slider from contacting the surface of the disk when the disk isslowed to a stop. Without unloading, as the disk slows to a stop, theairflow over its surface will lessen and the slider will stop flying. Atthis point, the slider will drop to contact and test upon the disksurface. Slider contact with the surface of the disk causes both theslider and the disk surface to sustain some wear. Further, with theslider resting on the disk, when the disk is spun up again there willexist stiction between the slider and the surface of the disk. Stictionmay cause structural damage to the delicate head gimbal assembly.Stiction causes further wear of the slider and disk surface as well asthe load on the motor turning the disk.

During the “load” portion of the load/unload operation the head gimbalassembly is lowered down from its rest towards the disk. With the diskspinning sufficiently, the slider will begin flying as it is lowered tothe surface of the disk.

Load/unloading can occur by having a tab on the head gimbal assemblywhich contacts and is lifted by, a load/unload ramp. As the tab is movedalong the ramp it is raised increasingly further up from the disksurface. This in turn raises the slider up from the surface and allowsthe disk to be stopped without the slider landing and resting on thedisk surface.

The other approach to increasing the overall disk storage has been toincrease the number of disks in the disk drive's disk stack. However, asadditional disks are added to the stack, the spacing between the disksdecreases. Therefore, the disk spacing can only be decreased a certainamount. This amount is determined by the height of the portion of thehead gimbal assembly which must fit between the disks.

In a disk drive having a load/unload ramp, the space between disks islimited by the height of lifter tabs of the head gimbal assemblies.Specifically, the height of the head gimbal assembly is defined by theamount which the lifter tab projects above the rest of the gimbalassembly. The lifter tab rises relative to the rest of the head gimbalassembly to allow access by the load/unload ramp. As such, the height ofthe lifter tab directly limits the spacing between disks, which in turnlimits the disk stack density. Therefore, a need exists for a headgimbal assembly with a low overall profile.

Thus, a head gimbal assembly with improved head-disk interface is soughtwhich will permit increased data storage by allowing for both greaterrecording density and closer disk stacking. To provide increasedrecording density without increasing damage caused by contacts of theslider to the disk caused by external shocks or jolts, the head gimbalassembly must employ an apparatus to limit the slider's motion. Also,the profile of the head gimbal assembly must be low enough to allow thedisks in the disk stack to be placed closer together to increase thestack density. However, the head gimbal assembly must still be capableof load/unload operations to reduce slider-disk wear and stiction.

SUMMARY OF THE INVENTION

With the present invention greater data storage can be achieved byemploying a combination of a load/unload mechanism and by increasing thestack density of the disk stack. The recording density can be increasedby allowing lower flying heights of the slider without increasingcontacts between the slider and the disk surface. Contacts between theslider and the disk surface are prevented by limiting the pitching,rolling and vertical displacement of the slider relative to thesupporting structure of the head gimbal assembly. Further, contacts canalso be avoided by maintaining a positive pitch of the slider during theunloading process. The disk stack density is increased by allowing thedisks to be positioned closer together. This closer spacing is achievedby configuring the head gimbal assembly to have a low overall height orprofile. This low profile is achieved by reshaping the lifter tab so itis lower but such that it still allows for load and unload operations.The head gimbal assembly is also specifically designed to allow forrelatively easy, quick and inexpensive manufacture.

The apparatus of the present invention is embodied in a is head gimbalassembly for use in a disk drive having a load/unload ramp. The headgimbal assembly includes a load beam having a pivot point, aflexure/slider assembly having a flexure and a slider, a limiter mountedbetween the flexure/slider assembly and the load beam, and a lifter tabextending from the load beam so as to be engagable with the load/unloadramp. The flexure is connected to the load beam and to the slider. Theslider is positioned by the flexure to be capable of moving about thepivot point. The limiter is positioned to limit movement of theflexure/slider assembly relative to the load beam. The head gimbalassembly can have a low profile by having the lifter tab extend from theload beam substantially at or below the upper surface of the load beam.

In one embodiment, the head gimbal assembly includes a load beam havinga pivot point, two leading edge limiter stops and two trailing edgelimiter stops. A flexure/slider assembly includes a flexure and aslider. The slider in turn has a leading edge, a trailing edge and twosides positioned between the leading and trailing edges. The slider isconnected to the flexure and resiliently urged by the flexure againstthe pivot point, such that the slider may pitch and roll about the pivotpoint and can be displaced downward from the pivot point. Theflexure/slider assembly has two leading edge limiter tabs positionednear each side of the slider leading edge to contact the two leadingedge limiter stops as the slider leading edge is moved beyond apredefined leading edge range of motion. The flexure/slider assemblyalso has two trailing edge limiter tabs positioned near the slidertrailing edge and each side of the slider, to contact the two trailingedge limiter stops as the slider trailing edge is moved beyond apredefined trailing edge range of motion. This embodiment also includesthe lifter tab which extends from the load beam so as to be engagablewith the load/unload ramp.

The method of manufacture of the present invention includes: obtaining aload beam having a base, two side beams extending from the base and twotabs extending forward from each side beam, where the base, the sidebeams and the tabs are substantially in a common plane; attaching aflexure/slider assembly to the load beam; bending the load beam atlocations between each tab and each side beam, such that the tabs aremoved to a position out of the common plane; and bending the load beamat locations between each side beam and the base, such that the sidebeams are moved to a position out of the common plane.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing the head gimbal assembly, actuatorarm, disk and load/unload ramp.

FIG. 2 is a perspective view showing a close-up of the head gimbalassembly.

FIG. 3 is a perspective view showing the head gimbal assembly.

FIG. 4 is a cross-section view showing the head gimbal assembly.

FIG. 5 is a perspective view showing an alternative embodiment of thepresent invention.

FIGS. 6 a-d is a set of cross-section views showing the head gimbalassembly during an unload operation.

FIGS. 7 a-e is a set of perspective views showing the manufacture of thehead gimbal assembly.

FIG. 8 is a flow chart setting forth the method of manufacture.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the preferred embodiments the invention is embodied in a head gimbalassembly (HGA). The head gimbal assembly includes an apparatus forlimiting the pitching, rolling and vertical displacement of the sliderrelative to the supporting structure of the head gimbal assembly. Thislimiting apparatus reduces the possibility of damage to the head gimbalassembly and disk from collisions between the slider and disk caused byshocks or jolts to the disk drive from external sources and themanufacturing process. Collisions are also avoided as the head gimbalassembly is configured to produce a positive pitch of the slider duringload and unload operations. The head gimbal assembly is also configuredto have a low overall height. This height reduction is achieved byreducing the height of the lifter tab in a manner which still allows forload and unload operations. The low profile of the head gimbal assemblyallows for a significant increase in stack density. That is, the lowprofile allows for increased data storage as the disks can be spacedcloser together, allowing more disks to be held in the same sized diskstack. The head gimbal assembly is also specifically designed to allowfor relatively easy, quick and inexpensive manufacture.

Description of Relevant Disk Drive Components:

The relevant components of the disk drive include the disk 2 and thehead stack assembly (HSA) 10. As shown in FIG. 1, the disk 2 includes adisk surface 4 and a disk outside edge 6. The head stack assembly 10includes a support arm 12 and a head gimbal assembly or HGA 16. The headstack assembly 10 can move from side to side to position the slider 20over a desired position on the disk 2. Also shown in FIG. 1 is aload/unload ramp 64, which operates to receive the head gimbal assembly16 and lift up the head gimbal assembly 16, with the slider 20, wellabove the disk surface 4.

Description of the Apparatus:

The primary components of the head gimbal assembly 16 includes a slider20, a flexure 30, and a load beam 40 with a lifter tab 60. Theseelements are shown in FIGS. 2 and 3.

The slider 20 includes a leading edge 22, a trailing edge 24, aread/write head 26 and sides 28. In the preferred embodiment, the slider20 is an “air bearing slider”. An air bearing slider is a device whichis specifically shaped so when it is placed into the airflow existingclose to the surface of a rotating disk, the slider will provide alifting force to cause it to fly above the disk. The slider 20 operatesto carry the read/write head 26 over the disk surface 4.

As shown in FIGS. 2 and 3, the slider 20 is rectangular in shape.Normally, slider 20 is positioned such that when it is in an airflow,the air generally flows first past the leading edge 22, then past sides28 and lastly past trailing edge 24. The leading edge 22 and trailingedge 24 are generally kept perpendicular with the airflow and sides 28generally parallel to the airflow. The slider 20 is attached to the restof the head stack assembly 10 such that it is free to pivot in bothpitch and roll, allowing the slider 20 to be free to fly. The headgimbal assembly 16 typically applies a downward force on the slider 20.In one embodiment this downward force is about 2.5 g.

The flexure 30 is an element that attaches the slider 20 to the rest ofthe head stack assembly 10. As can be seen in FIG. 2, the flexure 30 isrigidly attached to the slider 20 at the slider's upper surface 21. Theflexure 30 is also rigidly mounted to the load beam 40 of the head stackassembly 10 at a flexure mount 32, as shown in FIG. 3. The flexure 30 iscomprised of a relatively flexible material which is stiff enough tourge the slider 20 against a pivot point 47 of the load beam 40 and toresiliently urge the slider 20 to a desired attitude relative to thedisk surface 4. However, the flexure 30 is also flexible enough that theslider 20 can deflect in pitch and roll as necessary to allow the slider20 to fly in the airflow above the disk surface 4 when disk 2 isrotating.

As shown in FIG. 3, the flexure 30 is mounted to the load beam 40forward of the pivot point 47 at the flexure mount 32. In oneembodiment, the flexure 30 is attached to the load beam 40 at two weldpoints positioned along the length of the load beam 40. From its mount32, the flexure extends back to its attachment to the slider 20. Theflexure 30 is mounted to the load beam 40 such that it is deformedsufficiently from an initial shape to continuously urge the slider 20 ina substantially vertical direction up against the pivot point 47. Theflexure 30 also urges the slider 20 to have a positive pitch (leadingedge up relative to the trailing edge) when taking off from the disk 2.

The flexure 30 includes leading edge limiter tabs 36 and trailing edgelimiter tabs 38. As seen in FIGS. 2 and 3, the leading edge limiter tabs36 extend from the slider 20 at or near its leading edge 22. Likewise,the trailing edge limiter tabs 38 extend out from the slider 20 at ornear its trailing edge 24. The limiter tabs 36 and 38 each arepositioned above stops of the load beam 40 which act to limit movementof the limiter tabs 36 and 38. With the limiter tabs 36 and 38positioned at or near each end and at each side of the slider 20, theslider 20 is limited in its movement at each of its four corners.

The load beam 40 provides support to the other elements of the headgimbal assembly 16. The load beam 40 is a relatively rigid member whichacts to carry the loads imparted to, and generated by, the head gimbalassembly 16. As shown in FIGS. 2 and 3, the load beam 40 is part of thehead gimbal assembly 16. Load beam 40 extends outward from itsattachment to the support arm 12 to the slider 20. By actuation of thesupport arm 12, the load beam 40, carrying the slider 20, allows slider20 to be positioned across the disk surface 4. Moving the slider 20across the disk surface 4, allows a read/write head 26, mounted onto theslider 20 (preferably at the trailing edge), to read or write dataacross the entire usable portion of disk surface 4.

The load beam 40 includes: a pivot point 47, a first bend 44, a base 46,a forward second bend 48, a rear second bend 49, leading cross beam 50,side beams 52, a trailing cross beam 54, leading edge limiter stops 56,trailing edge limiter stops 58 and the lifter tab 60. These componentsare shown in FIGS. 2, 3 and 4.

The base 46 operates to provide a platform for both the pivot point 47which is mounted to the underside of the base 46 and for the leadingcross beam 50 which extends out horizontally on each side of the base46. The pivot point 47 can be a dimple formed out of the base 46. Theleading cross beam 50 extends far enough outward to extend past eachside 28 of the slider 20. At each outside ends of the leading cross beam50 are the forward second bends 48. The forward second bends 48 anglethe beam from a substantially horizontal orientation to a substantiallyvertical orientation. At the lower end of each of the forward secondbends 48 are side beams 52. The side beams 52 run from the forwardsecond bends 48 aft to each of the rear second bends 49. The side beams52 substantially parallel each of their neighboring slider sides 28. Theside beams 52 have sufficiently load capacity to carry the loads of theload beam 40 and to provide sufficient stiffness to prevent or limitdeflection of the load beam 40 during load and unload operations. At thetrailing edge of the side beams 52 the beams are connected to each ofthe rear second bends 49. At each of the rear second bends 49 the beambends back to being substantially horizontal to connect to the trailingcross beam 54. The trailing edge cross beam 54 extends across betweenboth of the rear second bends 49.

As shown in both FIGS. 2 and 3, the base 46, leading cross beam 50, sidebeams 52 and trailing cross beam 54 define an opening 42. At the forwardend of each side beam 52 are located the first bends 44. At each firstbend 44 the beam bends to extend in front of and substantially parallelto the slider leading edge 22 to form each of the leading edge limiterstops 56. As can be seen in FIGS. 2 and 3 the limiter stops 56 extendfrom each first bends 44 inward towards one another. The leading edgelimiter stops 56 are each positioned to receive a leading edge limitertab 36. Receiving both the leading edge limiter tabs 36 acts to limitthe downward pitch and translation of the slider 20. Receiving onelimiter tab 36 on one limiter stop 56 can act to limit the rotationalmotion of the slider 20. Also, by contacting the leading edge limitertabs 36 to the limiter stops 56 loads imparted on the slider 20 can betransferred to the load beam 40 through the limiter stops 56. Thisprotects the flexure 30 from damage (e.g. dimple separation or bendingof the flexure) which could otherwise result from excessivedisplacements of, and/or excessive loads upon, the slider 20 and flexure30.

Although other embodiments of the load beam 40 can be used, theaforementioned configuration allows for easier manufacture, providesincreased stiffness and allows for any possible post-assemblyadjustments to the head gimbal assembly 16. This embodiment of the loadbeam 40 allows the load beam 40 to be manufactured from a single sheetof material which is bent only two times during manufacture.

As shown in FIG. 5, an alternative embodiment of the load beam 40includes eliminating the opening 42. In this embodiment, the base 46′extends across the area of the opening 42, connecting with the leadingcross beam 50, the trailing cross beam 54 and the side beams 52. Twosmall limiter openings 43 are provided in the extended base 46′ aboutthe trailing edge limiter tabs 38 to allow for vertical movement of thelimiter tabs 38. Because the limiter openings 43 allow the trailinglimiter 38 to move within the openings 43, the slider 20 continues to beable to pitch, roll and translate vertically relatively freely withinthe range defined by the interaction of the trailing edge limiter tabs38, the limiter openings 43 and the trailing edge limiter stops 58. Thisalternative embodiment provides the advantage of increased stiffness ofthe load beam in both the vertical and lateral directions.

Between the load beam 40 and the slider 20 is a pivot point or dimple47, as shown in FIG. 4. Although the pivot point 47 can be any of avariety of shapes, in one embodiment the pivot point 47 is asemi-spherical shape which allows the slider 20 to pitch and roll aboutthe pivot point 47. The pivot point 47 acts as a gimbal for movement ofthe slider 20. The pivot point 47 positions the slider 20 and flexure 30sufficiently below the underside of the load beam 40 to allow enoughroom to accommodate the deflections associated with the flight of slider20. Although contacting the pivot point 47, neither the slider 20 northe flexure 30 are attached to the pivot point 47. Instead, the slider20 and flexure 30 are resiliently maintained up against the pivot point47 by deflection (e.g. pre-loading) of the flexure 30.

As noted, the flexure 30 is comprised of a relatively flexible materialwhich resiliently urges the slider 20 in a desired position and attitudeand allows the slider 20 to pitch and roll about the pivot point 47 asnecessary to allow the slider 20 to fly. In one embodiment, thethickness of flexure 30 is about a third of that of the load beam 40,making the flexure 30 about twenty-seven (27) times more flexible (in avertical direction) than the load beam 40.

As shown in FIGS. 2 and 3, the leading edge limiter tabs 36 of flexure30 are positioned above the leading edge limiter stops 56, such thatwhen the slider 20 pitches downward, the limiter tabs 36 contact thestops 56 and the downward pitching motion of the slider 20 isrestrained. With the limiter tabs 36 in contact with the stops 56, theloads acting to force the slider 20 to pitch downward are transferred tothe load beam 40. This protects the relatively weaker and more easilydeformed flexure 30 from damage which might result from the flexure 30carrying the loads. In other words, transferring the load from theflexure 30 to the load beam 40 protects the flexure 30 from damage dueto a displacement beyond the elastic limit of the flexure 30.

Likewise, the trailing edge limiter tabs 38 act to protect the flexure30 from damage. The trailing edge limiter tabs 38 extend out from thesides of the slider 20 at or near its trailing edge 24. The limiter tabs38 are positioned above each of the side beams 52, such that as theslider 20 is pitched upwards, the limiter tabs 38 will come in contactwith the upper surface 55 of each side beam 52. The portions of eachupper surface 55 which receives the limiter tabs 38 are the trailingedge limiter stops 58. The contact of the limiter tabs 38 with thelimiter stops 58 retrains the pitching motion of the slider 20. As such,the loads forcing the slider 20 to pitch up are transferred to the loadbeam 40, protecting the flexure 30 from being damaged from displacementsbeyond its elastic limit.

The leading edge limiter tabs 36 and trailing edge limiter tabs 38 alsofunction to limit the roll of the slider 20. Since each limiter tab isplaced at or near the side of the slider 20, as the slider 20 rolls toone side, that side will drop and the leading edge limiter tab 36 andthe trailing edge limiter tab 38 on that side of the slider 20, willcontact the leading edge limiter stop 56 and trailing edge limiter stop58 on that same side. This will restrain the rolling of the slider 20 inthat direction. With the limiter tabs 36 and 38 in contact with thestops 56 and 58, the load on the flexure 30 will be transferred to theload beam 40.

Besides limiting the pitching and rolling of the slider 20, the limitertabs 36 and 38 and limiter stops 56 and 58 also act to limit verticaltranslations of the slider 20. Since the slider 20 and flexure 30 areresiliently urged against the pivot point 47, but not attached to thepivot point 47, the slider 20 can be displaced in a vertical direction(downward) from the pivot point 47. Such a downward displacement canresult from a variety of sources, including an external shock or jolt tothe disk drive, handling during manufacture or as a result of theunloading of the head gimbal assembly 16. The downward displacement ofthe slider 20 is limited by leading edge limiter tabs 36 and thetrailing edge limiter tabs 38 contacting the leading edge limiter stops56 and the trailing edge limiter stops 58 respectfully. Again, as withthe pitch and roll limits, the loads on the flexure 30 from the verticaldisplacement of the slider 20, transfer to the load beam 40 after thelimiter tabs 36 and 38 contact the limiter stops 56 and 58.

In an alternative embodiment, the head gimbal assembly 16 can employthree (3) limiter tabs. In one such embodiment, the trailing edgelimiter tabs 38 remain as previously described but only one leading edgelimiter tab 36 is used. This embodiment continues to limit the pitch,roll and vertical displacement of the slider 20.

As can be seen in FIGS. 2 and 3, extending from the trailing cross beamoutward is the lifter tab or load/unload tab 60. The lifter tab 60operates in conjunction with a load/unload ramp or lifter 64 to allowthe head gimbal assembly 16 to be lifted up away from the surface ofdisk 2 when the head stack assembly 10 is not in use. The action oflifting the head gimbal assembly 16 from the disk surface or “parking”the head stack assembly 10, is advantageous as it protects both the disk2 and the head gimbal assembly 16 when not in use, from damage caused byexternal shocks or jolts to the disk drive.

As shown in FIG. 1, the load/unload ramp 64 has an edge 68 and aninclined surface 66 (inclined relative to the surface of disk 2). Theinclined surface 66 extends down to near to the disk surface 4. Theload/unload ramp 64 must extend low enough such that its edge 68 willslide under at least a portion of the lifter tab 60. The load/unloadramp 64 can be either fixed or movable. In one embodiment theload/unload ramp 64 is fixed in its position, as shown in FIG. 1. Theload/unload ramp 64 is positioned at or near the outside edge 6 of thedisk 2 in a position to receive the lifter tab 60 when the head stackassembly 10 is swung far enough to contact the load/unload ramp 64. Inanother embodiment the load/unload ramp 64 is movable. The load/unloadramp 64 can move over the disk surface 4 to receive the load/unload ramptab 60. The movable load/unload ramp 64 parks the head gimbal assembly16 by moving under the lifter tab 60 and raising the head gimbalassembly 16 above the disk 2. The movable load/unload ramp 64 releasesthe head gimbal assembly 16 by moving back towards the outside edge 6 ofthe disk 2.

As shown in FIG. 3, the lifter tab 60 has typically a semi-circularcurved lower surface 62 which facilitates the contact of the lifter tab60 with the load/unload ramp 64, as well as the movement of the tab 60along the inclined plane surface 66.

The load/unload ramp 64 allows load/unload operations of the disk drive.As noted, the head gimbal assembly 16 applies a load in a substantiallydownward direction on the slider 20. This loading helps to keep theslider 20 close to the disk surface 4 and increases the stability of theslider 20 in flight. As the slider 20 is flying in the airflow abovedisk 2 (rotating to create the airflow), slider 20 creates a liftingforce which counteracts the load imparted by the head gimbal assembly16. As the lifter tab 60 contacts and is received by the load/unloadramp 64, the load of head gimbal assembly 16 is transferred onto theload/unload ramp 64. With the lifter tab 60 resting on the load/unloadramp 64 the head gimbal assembly 16 is unloaded. When the lifter tab 60is not resting on the load/unload ramp 64 the head gimbal assembly 16 isloaded. When the head gimbal assembly 16 is loaded and the disk 2spinning, at a rate fast enough to create a sufficient airflow to causethe slider 20 to fly, the lift force from the slider 20 will counter theload of head gimbal assembly 16. Therefore, an unload operation occurswhen the head gimbal assembly 16 (via the lifter tab 60) is parked ontothe load/unload ramp 64 and a load operation occurs-when the head gimbalassembly 16 is moved off the load/unload ramp 64. To allow for fastload/unload operations the load beam 40 must be sufficiently rigid toavoid excessive deformations.

As can be seen in FIGS. 6 a-d, the configuration of the head gimbalassembly 16, including the positioning of the limiter tabs 36 and 38 andtheir respective stops 56 and 58, provide that the slider 20 will have apositive pitch attitude when the head gimbal assembly 16 is unloaded. Apositive pitch of slider 20 during unloading reduces the potential fordamage caused by the slider leading edge 22 contacting the disk surface4. As shown in FIG. 6 a, as the unload process begins, the lifter tab 60contacts the load/unload ramp 64 which begins to apply a substantiallyvertical force onto the lifter tab 60. This force in conjunction withthe load force from the head gimbal assembly 16, causes the load beam todeform slightly. The slider 20 is still in flight and free to pitch androll about the pivot point 47.

As shown in FIG. 6 b, as the lifter tab 60 moves further up the inclinedsurface 66, the load exerted on the lifter tab 60 increases. This inturn increases the deformation of the load beam 40. At this point theleading edge limiter tabs 36 contact the leading edge limiter stops 58and the slider 20 is restrained moving past the stop in a negative pitchdirection. The trailing edge limiter is not in contact with the trailingedge limiter stop 58. As such, the slider is still free to pitch in apositive direction.

Next, as shown in FIG. 6 c, as the lifter tab 60 moves further upinclined surface 66 the load on lifter tab 60 and the resultingdeformation of load beam 40 increases. With the slider leading edge 22held in place by contact of the leading edge limiter 36 with the leadingedge limiter stop 56, the relative downward movement of the pivot point47, caused by the deformation of the load beam 40, forces the slider 20into a positive pitch attitude. This forced positive pitch prevents theslider 20 from pitching in a negative direction which would otherwiseallow the slider leading edge 22 to drop and potentially contact thedisk surface 4. At this stage in the unload process the trailing edgelimiter 38 is not in contact with the trailing edge limiter stop 58.

As seen in FIG. 6 d, the unload process is complete and the load beam 40is deformed sufficiently to cause the trailing edge limiter 38 tocontact the limiter stop 58.

During loading of the head gimbal assembly 16 the process is reversedand the load beam 40 is lowered towards the disk surface 4 with apositive pitch attitude.

As can be seen in FIGS. 2-4, in the preferred embodiment, the lifter tab60 does not extend above the upper surface 41 of the load beam 40. Thisprovides the lifter tab 60 with a relatively low profile. The lifter tab60 does not increase the overall head assembly height H, which as seenin FIG. 4, is the distance between the upper surface 41 of the load beam40 and the lowest point on the bottom 29 of the slider 20. As shown inFIG. 4, the low profile of the lifter tab 60 allows for relatively closestacking of disks 2. Allowing a greater disk stack density and increasedoverall data storage of the disk drive.

Description of Method of Manufacture:

As shown in FIG. 8, the preferred embodiments of the apparatus can bemanufactured by a method which includes: obtaining a load beam having abase, at least one side beam extending from the base and at least onetab extending from the at least one side beam, wherein the base, atleast one side beam and the at least one tab are substantially in acommon plane 100; attaching a flexure/slider assembly to the load beam110; bending the load beam between the at least one tab and the at leastone side beam, such that the at least one tab is positioned out of thecommon plane 120; and bending the load beam between the at least oneside beam and the base, such that the at least one side beam ispositioned out of the common plane 130. This method is also shown inFIGS. 7 a-e.

The step of obtaining a load beam 100 can be performed in many waysinclude stamping the load beam 40 out from a sheet of material of anuniform thickness. As seen in FIG. 7 a, the load beam 40 can be cut froma single sheet of material, with opening 42 cut from the center and withthe side beams 52 and the leading edge limiter stop tabs 56.

Next, the lifter tab 60 can be formed as shown in FIG. 7 b. This stepinvolves bending the flat lifter tab 60 into a curved shape to such thatduring load/unload operations the load/unload ramp 64 can gain accessunder the lifter tab 60 to raise up the head gimbal assembly 16. Thelifter tab 60 is formed so to retain a low profile of the head gimbalassembly 16 by not rising above the upper surface of the load beam 40.

As shown in FIG. 7 c, the step of attaching the flexure/slider assemblyto the load beam 110 includes attaching the separately manufacturedflexure 30 and slider 20 assembly to the load beam 40. This attachmentis at flexure mount 32 and can be two welds along the length of the loadbeam 40. With the flexure 30 and slider 20 attached to the load beam 40,the opening 42 allows access for any possible post-assembly adjustmentsto elements such as the flexure 30, limiter tabs 36 and 38. Further, inthe event the wiring to the read/write head is done after the assemblyof the head gimbal assembly 16 (instead of during manufacture of theflexure/slider assembly), the opening 42 allows for easier attachment ofthe wiring.

The step of bending the load beam between the at least one tab and theat least one side beam 120 includes bending both of the leading edgelimiter stops 56. As shown in FIG. 7 d, the leading edge limiter stops56 are bent downward to a substantially vertical orientation at firstbends 44. In one embodiment of the method, the bend is made over aspecifically designed mandrel placed under the unbent load beam 40 atthe location of the first bends 44. In an alternative step, instead ofbending the two leading edge limiter stops 56 at the same time, thisstep can involve two separate bends. First one side of the load beam 40is bent and then the other.

The step of bending the load beam between the at least one side beam andthe base 130 includes bending the load beam is 40 to create both of theside beams 52. As seen in FIG. 7 e, to complete the manufacture of thehead gimbal assembly 16, the side beams 52 are bent downward to asubstantially vertical orientation at each forward second bend 48 andrear second bend 49. In the preferred embodiment, when the load beam 40is cut, the side beams 52 are made at least wider than the thickness ofthe load beam. This provides that when the side beams 52 are bent to avertical orientation, their vertical load capacity and stiffness aregreater than if the beam had remained in its original unbentorientation. In one embodiment of the method, the second bends are madeover a specifically designed mandrel placed under the unbent load beam40 at the location of the each forward second bend 48 and rear secondbend 49. The bending of the side beams 52 causes the leading edgelimiter stops 56 to be rotated up and under the base 46 and forward ofthe slider 20, as shown in FIG. 7 e. With the leading edge limiter stops56 so positioned by the second bend, they are able to receive theleading edge limiter tabs 36 when the slider 20 is sufficientlydisplaced by either pitching, rolling, a vertical displacement or acombination thereof. In an alternative step, instead of bending the twoside beams 52 at the same time, this step can involve two separatebends. First one side of the load beam 40 is bent and then the other.

While the invention has been described in detail by specific referenceto preferred embodiments, it is understood that the above description isnot limiting of the disclosed invention and variations and modificationsthereof may be made without departing from the true spirit and scope ofthe invention.

1. A method of manufacture comprising: A. obtaining a load beam having abase, at least one side beam extending from the base and at least onetab extending from the at least one side beam, wherein the base, atleast one side beam and the at least one tab are substantially in acommon plane; B. attaching a flexure/slider assembly to the load beam;C. bending the load beam between the at least one tab and the at leastone side beam, such that the at least one tab is positioned out of thecommon plane, and such that the tab and the side beam are substantiallyorthogonal to one another; and D. bending the load beam between the atleast one side beam and the base, such that the at least one side beamis positioned out of the common plane, and such that both the tab andthe side beam are substantially orthogonal to the base.
 2. The method ofclaim 1, wherein the step of obtaining the load beam comprises stampingthe load beam out of a sheet of material.
 3. The method of claim 1,wherein the step of bending the load beam between the at least one taband the at least one side beam comprises bending the at least one tab ina first direction so the at least one tab is in a position substantiallyperpendicular to the common plane.
 4. The method of claim 3, wherein thestep of bending the load beam between the at least one side beam and thebase comprises bending the at least one side beam in the first directionso that the at least one side beam is in a position substantiallyperpendicular to the common plane.
 5. The method of claim 1, wherein theload beam further comprises a lower surface and wherein the step ofattaching the flexure/slider assembly to the load beam comprisesattaching the flexure/slider to the lower surface of the load beam. 6.The method of manufacture of claim 1 wherein the load beam includes alifter tab portion and the method further comprises deforming the liftertab portion to form a lifter tab.
 7. The method of manufacture of claim6 wherein the base and the lifter tab portion are integral.
 8. Themethod of manufacture of claim 1 wherein obtaining the load beamincludes stamping the load beam from a sheet.
 9. The method ofmanufacture of claim 1 wherein bending the load beam is performed over amandrel.
 10. The method of manufacture of claim 1 wherein attaching theflexure/slider assembly to the load beam is performed before bending theload beam between the at least one tab and the at least one side beam.11. The method of manufacture of claim 1 wherein bending the load beambetween the at least one tab and the at least one side beam is performedbefore bending the load beam between the at least one side beam and thebase.
 12. The method of manufacture of claim 1 wherein attaching theflexure/slider assembly to the load beam includes mounting a flexure ofthe flexure/slider assembly to the load beam forward of a pivot of theload beam, the flexure including a edge limiter tab.
 13. The method ofmanufacture of claim 12 wherein bending the load beam between the atleast one side beam and the base includes positioning the at least oneside beam beneath the edge limiter tab.
 14. The method of manufacture ofclaim 12 wherein bending the load beam between the at least one sidebeam and the base includes positioning the flexure between the at leastone tab and the base.
 15. A method of manufacture comprising: A.obtaining a load beam having a base, at least one side beam extendingfrom the base and at least one tab extending from the at least one sidebeam, wherein the base, at least one side beam and the at least one tabare substantially in a common plane; B. attaching a flexure/sliderassembly to the load beam; C. bending the load beam about a first axisbetween the at least one tab and the at least one side beam, such thatthe at least one tab is positioned out of the common plane; and D.bending the load beam about a second axis between the at least one sidebeam and the base, the second axis being substantially orthogonal to thefirst axis, such that the at least one side beam is positioned out ofthe common plane.
 16. The method of manufacture of claim 15 wherein theload beam includes a lifter tab portion and the method further comprisesdeforming the lifter tab portion to form a lifter tab.
 17. The method ofmanufacture of claim 16 wherein the base and the lifter tab portion areintegral.
 18. The method of manufacture of claim 15 wherein obtainingthe load beam includes stamping the load beam from a sheet.
 19. Themethod of manufacture of claim 15 wherein bending the load beam isperformed over a mandrel.
 20. The method of manufacture of claim 15wherein attaching the flexure/slider assembly to the load beam isperformed before bending the load beam between the at least one tab andthe at least one side beam.
 21. The method of manufacture of claim 15wherein bending the load beam between the at least one tab and the atleast one side beam is performed before bending the load beam betweenthe at least one side beam and the base.
 22. The method of manufactureof claim 15 wherein attaching the flexure/slider assembly to the loadbeam includes mounting a flexure of the flexure/slider assembly to theload beam forward of a pivot of the load beam, the flexure including aedge limiter tab.
 23. The method of manufacture of claim 22 whereinbending the load beam between the at least one side beam and the baseincludes positioning the at least one side beam beneath the edge limitertab.
 24. The method of manufacture of claim 22 wherein bending the loadbeam between the at least one side beam and the base includespositioning the flexure between the at least one tab and the base.
 25. Amethod of manufacture comprising: A. obtaining a load beam having abase, at least one side beam extending from the base and at least onetab extending from the at least one side beam, wherein the base, atleast one side beam and the at least one tab are substantially in acommon plane; B. attaching a flexure/slider assembly to the load beam;C. after attaching the flexure/slider assembly, bending the load beambetween the at least one tab and the at least one side beam, such thatthe at least one tab is positioned out of the common plane; and D.bending the load beam between the at least one side beam and the base,such that the at least one side beam is positioned out of the commonplane.
 26. The method of manufacture of claim 25 wherein the load beamincludes a lifter tab portion and the method further comprises deformingthe lifter tab portion to form a lifter tab.
 27. The method ofmanufacture of claim 26 wherein the base and the lifter tab portion areintegral.
 28. The method of manufacture of claim 25 wherein obtainingthe load beam includes stamping the load beam from a sheet.
 29. Themethod of manufacture of claim 25 wherein bending the load beam isperformed over a mandrel.
 30. The method of manufacture of claim 25wherein bending the load beam between the at least one tab and the atleast one side beam is performed before bending the load beam betweenthe at least one side beam and the base.
 31. The method of manufactureof claim 25 wherein attaching the flexure/slider assembly to the loadbeam includes mounting a flexure of the flexure/slider assembly to theload beam forward of a pivot of the load beam, the flexure including aedge limiter tab.
 32. The method of manufacture of claim 31 whereinbending the load beam between the at least one side beam and the baseincludes positioning the at least one side beam beneath the edge limitertab.
 33. The method of manufacture of claim 31 wherein bending the loadbeam between the at least one side beam and the base includespositioning the flexure between the at least one tab and the base.